A step forward in predicting volcanic eruptions

There are two main things most people would like to know about particular volcanoes: when is the next eruption and how big will that eruption be? Scientists in Iceland have taken another step forward in monitoring volcanoes to best predict when they will erupt and even warn people of the size of the coming eruption.

In May 2011, a volcano in Iceland named Grímsvötn erupted. It generated a 12-mile-high plume of volcanic debris that temporarily grounded airplanes as far away as Great Britain. The problem wasn’t as great, though, as that which had occurred a year earlier, when another Ic...